A gas manifold for a convection conveyor oven includes an elongated housing having a wall that at least partially encloses an interior volume; a gas inlet in fluid communication with the interior volume and extending through the wall; a plurality of gas outlets in fluid communication with the interior volume and extending through the wall; a plurality of seat inserts removably coupled with a plurality of gas outlets; a plurality of valve openings formed in the wall and aligned opposite the plurality of gas outlets; and at least one valve removably coupled to the wall and aligned with a first valve opening, wherein the valve is aligned with a first gas outlet and has a first position in which a first seat insert is not in fluid communication with the gas inlet.

A gas manifold for a convection conveyor oven includes an elongated housing having a wall that at least partially encloses an interior volume; a gas inlet in fluid communication with the interior volume and extending through the wall; a plurality of gas outlets in fluid communication with the interior volume and extending through the wall; a plurality of seat inserts removably coupled with a plurality of gas outlets; a plurality of valve openings formed in the wall and aligned opposite the plurality of gas outlets; and at least one valve removably coupled to the wall and aligned with a first valve opening, wherein the valve is aligned with a first gas outlet and has a first position in which a first seat insert is not in fluid communication with the gas inlet.

A combination boiler provides heated water to a boiler loop and heated domestic hot water (DHW) to a DHW loop. A primary heat exchanger is connected to the boiler loop. A burner provides heat to the primary heat exchanger and an input fan supplies a fuel and air mixture to the burner. A secondary heat exchanger transfers heat energy from the boiler loop to a domestic water loop. A controller determines a boiler loop flow rate. The controller measures an input temperature of the boiler loop, an output temperature of the boiler loop, and a DHW output temperature of the domestic water loop. The controller determines a DHW input temperature and estimates a DHW flow rate. The input fan speed is initiated or operated according to a required heat output of the burner corresponding to the DHW flow rate.

Described is a device (11) for controlling the combustion of a burner (1), comprising: first means (12) for measuring the fuel flow rate (Vg); second means 13 for measuring the flow rate of the comburent (Va) first operator means (14) for controlling the opening of an inlet valve (5) as a function of the quantity of fuel to be supplied to the burner (1); second operator means (15) for controlling the comburent flow regulator means (8) as a function of the quantity of comburent to be supplied to the burner (1); According to this invention, the device (11) comprises a unit (16) for controlling the first operator means (14) and the second operator means (15) as a function of the values measured by the first measuring means (12) and by the second measuring means (13).